All banks in the Gaza Strip temporarily shut down on Thursday after men affiliated with the ruling group Hamas forced a local branch to cash some $500,000 in checks. Gaza bankers said Hamas sent the police to confiscate the money from a branch of the Palestine Investment Bank. They said the police were accompanied by members of a committee Hamas had appointed in 2009 to oversee the Palestine Investment Fund, which is run by the rival Palestinian government in the West Bank. The men confiscated checks from the fund, then ordered bank tellers to cash them, though the account did not contain enough money. The bankers spoke on condition of anonymity for fear of retribution. The Hamas Interior Ministry said the police helped to seize the money because the investment fund had improperly transferred money out of Gaza to the West Bank. Hamas denied that the money was taken at gunpoint.